In the Linux kernel, the following vulnerability has been resolved:

platform/chrome: cros_ec_uart: properly fix race condition

The cros_ec_uart_probe() function calls devm_serdev_device_open() before
it calls serdev_device_set_client_ops(). This can trigger a NULL pointer
dereference:

BUG: kernel NULL pointer dereference, address: 0000000000000000
...
Call Trace:
<TASK>
...
? ttyport_receive_buf

A simplified version of crashing code is as follows:

static inline size_t serdev_controller_receive_buf(struct serdev_controller *ctrl,
const u8 *data,
size_t count)
{
struct serdev_device *serdev = ctrl->serdev;

if (!serdev || !serdev->ops->receive_buf) // CRASH!
return 0;

return serdev->ops->receive_buf(serdev, data, count);
}

It assumes that if SERPORT_ACTIVE is set and serdev exists, serdev->ops
will also exist. This conflicts with the existing cros_ec_uart_probe()
logic, as it first calls devm_serdev_device_open() (which sets
SERPORT_ACTIVE), and only later sets serdev->ops via
serdev_device_set_client_ops().

Commit 01f95d42b8f4 ("platform/chrome: cros_ec_uart: fix race
condition") attempted to fix a similar race condition, but while doing
so, made the window of error for this race condition to happen much
wider.

Attempt to fix the race condition again, making sure we fully setup
before calling devm_serdev_device_open().
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Tue, 14 Jan 2025 17:00:00 +0000

Type Values Removed Values Added
First Time appeared Linux
Linux linux Kernel
Weaknesses CWE-362
CWE-476
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.9:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.9:rc2:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.9:rc3:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
Metrics cvssV3_1

{'score': 5.5, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}

cvssV3_1

{'score': 4.7, 'vector': 'CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H'}


Fri, 20 Dec 2024 08:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Wed, 11 Sep 2024 18:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Wed, 11 Sep 2024 13:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2025-05-04T09:09:37.893Z

Reserved: 2024-05-17T13:50:33.143Z

Link: CVE-2024-35977

cve-icon Vulnrichment

Updated: 2024-08-02T03:21:49.031Z

cve-icon NVD

Status : Analyzed

Published: 2024-05-20T10:15:12.340

Modified: 2025-01-14T16:36:51.467

Link: CVE-2024-35977

cve-icon Redhat

Severity : Moderate

Publid Date: 2024-05-20T00:00:00Z

Links: CVE-2024-35977 - Bugzilla

cve-icon OpenCVE Enrichment

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